When the magnitude of B is experimentally determined and this measurement is repeated n times, the results will be distributed around a mean value

A typical instrumental method of analysis involves several experimental measurements, each of which is subject to an indeterminate uncertainty and each of which contributes to the net indeterminate error of the final result. [Pg.499]

Figure 26-1 la is a plot of the relative standard deviation for experimentally determined concentrations as a function of absorbance. It was obtained with a spectrophotometer similar to the one shown in Figure 25-19. The striking similarity between this curve and curve A in Figure 26-10 indicates that the instrument studied is affected by an absolute indeterminate error in transmittance of about 0.003 and that this error is independent of transmittance. The source of this uncertainty is probably the limited resolution of the transmittance scale. |

At the present time, in most PCS instruments, dust is handled in two ways an experimentally measured, delayed baseline and/or a dust term in the calculation. The latter method usually assumes dust to be infinitely large with a zero diffusion coefficient. This leads to a constant, which is another way of saying a baseline. The problem with adjusting the baseline is that even a very small baseline uncertainty can lead to rather large errors in the distribution parameters as shown in the Appendix. A better procedure would be to reject dust before it contributed to the correlation function. [Pg.52]

The objective of this test was to present and analyze suitable experimental results for verif ying quantitatively the use of the above-mentioned three corrections with the W-3 correlation for predicting the DNB heat flux in a rod bundle. Uncertainties in the data due to instrument errors and heater rod fabrication tolerances [Pg.439]

Results of an analysis conducted on a hyphenated instrument are typically calculated from two or more experimental data sets, each of which carries some uncertainty due to random noise or experimental errors. It is therefore worthwhile determining the ways various uncertainties accumulate in the final output from a hyphenated instrument. For simplicity, let us assume that two in-line instruments measure two quantities jc and y which depend upon variables p, q, r for x, and s, t, u fory. [Pg.5]

Equation 26-6 shows that the uncertainty in a photometric concentration measurement varies in a complex way with the magnitude of the transmittance. The situation is even more complicated than suggested by the equation, however, because the uncertainty

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